Fuse systems serve to detonate the main charge (‘secondary’ of military ordnance) of a munition, a cartridge, or an ordnance (collectively referred to herein as ordnance) at the desired time or location. The fuse (or fuze) plays an essential safety role of preventing accidental detonation of the ordnance, making the ordnance safe to handle. There are a variety of technologies used in fuse systems. The fuses considered here are “programmable”: immediately prior to the ordnance being fired from a gun, timing or similar data is loaded into the fuse so that the fuse initiates detonation of the secondary charge of the ordnance at the desired time and/or location. One common approach to such a fuse system is to charge a capacitor, and then discharge it at the desired time across a thin wire to create sufficient local heating or a spark to ignite the primary explosive. On-board electronics or mechanical devices control the discharge timing. Fuses typically incorporate “g-switches” that prevent detonation until the fuse has been exposed to accelerations of a magnitude and time typically only encountered in a gun barrel. There are on-going efforts at fabricating Micro-Electrical Mechanical Switch (MEMS)-based g-switches.
Notwithstanding the advances made by these prior fuse systems, there is a continuing need to significantly reduce the size, improve the performance and safety of the overall ordnance fuse system.